1. Field of the Invention
The invention involves an apparatus for the aftertreatment of photopolymerizable printing plates with means to produce an environment with at least one predetermined condition and a transport device to bear the printing plates and to transport them through the apparatus.
2. Description of Related Art
Photopolymerizable printing plates are washed off after exposure, which polymerizes the exposed or unexposed areas, depending on the plate composition. Washoff removes the unpolymerized components of the printing plate. After washoff, the printing plates, which are sometimes also called stereotypes, usually have some residual moisture and residual tackiness, which must be removed in subsequent aftertreatments.
For example, EP 0 225 678 discloses blowing warm drying air over the printing plates after washoff and then positioning them for heat treatment. This aftertreatment occurs in the same apparatus where the washoff was conducted, that is, the printing plates have essentially the same velocity in drying as in washoff. As drying usually requires essentially more time than washoff, this results in a series of contradictory requirements. To be able to conduct the aftertreatment with the necessary care, the apparatus must be large enough for the plates to spend sufficient time in the apparatus. On the other hand, the apparatus must not exceed a size determined by cost and space considerations. Shortening the aftertreatment time or lengthening washoff time usually leads to unsatisfactory compromise solutions.
DE 30 04 735 A1 discloses an apparatus for simultaneously treating the surfaces of several printing plates, wherein the several printing plates are first collected on a carriage that has a series of carriers arranged one above the other. The loaded carriage is conveyed into the apparatus and remains there for a predetermined aftertreatment time in a first section. Then it is conveyed into a second section, where it remains similarly for a predetermined second treatment time. However, the batchwise loading of the apparatus has the disadvantage that not all of the printing plates can be treated immediately after the washoff process. Residual washoff liquid can remain active on the plates, whereby the desired result, specifically a printing plate with a predetermined relief, is undesirably modified. Furthermore, the disclosed apparatus requires additional plate handling, which hinders automating plate production, and requires space to collect the plates.